Jonnie Peacock is sat in one of Manchester's grander hotels, looking fashionable in slim-fit denim and boy band scuff-stubble and chuckling drily at a prophecy made by the Guardian after his 100m T44 Paralympics gold medal. In the giddy delirium of that September night, when the first breath of autumn was warmed by 80,000 people chanting his name, we suggested "his life is about to change in ways he cannot possibly imagine now".

When Peacock hears this he laughs, mutters a noncommittal "er", and then laughs again. "It has changed slightly," he concedes. "Luckily people don't recognise me without the blade on. I still do my shopping without being spotted."

After some prodding, he mentions the "cool" photoshoot for Attitude magazine, and a "cool" invite to the premiere of Skyfall. "Although everything went wrong that day. I arrived late as usual and then had to walk past Dame Judi Dench."

His grimace suggests she was not impressed. A meeting with actual rather than acting royalty to pick up his MBE has still not been arranged. "We haven't nailed that one down yet because I've been away, or training, or injured," he says of his future date with the Queen. "But I'm really excited about it."

While swanky parties have largely passed him by, Peacock's professional life has altered significantly since the Paralympics. He has had an ankle operation which has left him playing catch-up. He swapped the blade which helped him run a world record 10.85sec for the 100m T44 last year for a shorter and, he hopes, faster model. And, most surprisingly of all, he has left the world-renowned sprint coach Dan Pfaff, who guided him to Paralympic gold, because he could not face living in the United States.

"I went there for January but the American lifestyle is not for me," he admits. "So the less time I spend over there the better." He insists there was no falling-out with Pfaff, whom he describes as a "great coach", and says the facilities in Arizona were excellent too. It's just that it wasn't for him. "It was just too big a country," he says. "You have to drive two days to find places. By the end I was counting down the days to leave."

Britain's Jonnie Peacock crosses the line ahead of Arnu Fourie, third left, and Richard Browne, right, in the men's T44 100m final. Photograph: Tom Jenkins for the Guadian

Peacock, who turns 20 on Tuesday, has since moved to Loughborough to train with Steve Fudge and is much happier. "I'm definitely a home boy," he says. "And so far, so good. There are a few things we are trying to fix at the moment as well as adding extras that I didn't have last year." Go on … He chuckles again. "I can't give away all my training secrets."

He does, however, admit that he plans to add the 200m to his repertoire at some point – only just not yet. "You don't have to be fit to run 100m," he explains. "If you run it technically well then you are going to hold your speed. The furthest I ran in training last year was 120m and I'm pretty sure I had the better finish than most of the guys in London who were doing 200m reps. But I'm certainly a speed man at the moment."

This weekend Peacock will compete for the first time since London in front of 20,000 people on a specially built track in Deansgate, Manchester, for the BT Great CityGames. He is cautious about offering predictions for this season, given the injury and recent upheavals. But he is convinced that, eventually, he will beat his world record.

"I don't know what is possible," he says. "All I know is that I haven't gone nearly as quick as I should have, even last year." Is 10.5sec a realistic target? "Never say never. That's a time I would like to get down to in the future. It's funny, there's a certain American who keeps saying: 'I'm going to run 10.5.' And I'm like: 'Start saying that when you've broken 11 seconds.' You get a lot of these people saying things they will never achieve."

If that's a sly dig at Jerome Singleton, who proclaimed himself "the fastest amputee on the planet" before leaving London without a medal, then Peacock has much kinder words for Oscar Pistorius, who this week confirmed he would not be competing while he awaits trial for the alleged murder of his girlfriend Reeva Steenkamp.

Last year Peacock admitted he had "enormous respect" for Pistorius and, despite what has happened since, that has not changed. "My feeling is the same," he says. "I have great respect for what the man has done for the sport. I always will do. [What happened] is not going to change how he was with me. And at the end of the day, who knows what happened? We are just going to have to wait and see."

Has he spoken to him since his arrest? "No – I'm sure he has enough hassle and wants to be alone with himself. But there is a Paralympics after Oscar Pistorius; it's as simple as that. London has shown there are new faces in the sport and it's up to those people to push it on."

While Pistorius was keen to shatter boundaries by taking on able-bodied athletes, Peacock says it is not an priority for him. "It's something that people make out is a big deal, but it's not," he says. "I raced against able-bodied athletes last year. But the Olympics is an unrealistic goal for a Paralympic sprinter because you need an amazing start, and with a blade you don't necessarily have that."

Instead, he has more immediate concerns. "This year we've got BT Great CityGames Manchester and the Birmingham and London [meetings], so it's a wicked opportunity to be in front of the British crowd who I love." He laughs again, before reaching for his favourite adjective. "It's going to be cool. Really cool."

The BT Great CityGames Manchester is free to spectators and takes place in the city centre on Saturday 25 May. For more information go to www.greatcitygames.org